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Operating System Tools

Notes library API, permitting advanced developers to manage such transactions from programming
languages such as C or Python.

4.1 The Red Hat Package Manager (RPM)

RPM, the Red Hat Package Manager, is a powerful package manager that you can use to install,
update and remove packages. It allows you to search for packages and keeps track of the files that
come with each package. A system is built-in so that you can verify the authenticity of packages
downloaded from the Internet. Advanced users can build their own packages with RPM.

The Red Hat Package Manager (RPM) is an open packaging system, available for anyone to use,
which runs on Red Hat Linux as well as other Linux and UNIX systems. Red Hat, Inc. encourages
other vendors to use RPM for their own products. RPM is distributable under the terms of the
GPL.
For the end user, RPM makes system updates easy. Installing, uninstalling, and upgrading RPM
packages can be accomplished with short commands. RPM maintains a database of installed
packages and their files, so you can invoke powerful queries and verifications on your system.
If you prefer a graphical interface, you can use Gnome-RPM to perform many RPM commands.

During upgrades, RPM handles configuration files carefully, so that you never lose your
customisations — something that you will not accomplish with regular .tar .gz files.
For the developer, RPM allows you to take software source code and package it into source and
binary packages for end users. This process is quite simple and is driven from a single file and
optional patches that you create. This clear delineation of “pristine” sources and your patches
and build instructions eases the maintenance of the package as new versions of the software are
released.
An RPM package consists of an archive of files and meta-data used to install and erase the archive
files. The meta-data includes helper scripts, file attributes, and descriptive information about the
package.

Notes Packages come in two varieties: binary packages, used to encapsulate software
to be installed, and source packages, containing the source code and recipe necessary to
produce binary packages.

Many other distributions support RPM packages, among the popular ones Mandrake and SuSE
Linux. Apart from the advice for your distribution, you will want to read man RPM.
Most packages are simply installed with the upgrade option, whether the package is already
installed or not. The RPM package contains a complete version of the program, which overwrites
existing versions or installs as a new package.
New kernel packages, however, are installed with the install option which does not overwrite
existing version(s) of the package, least to be able to boot your system with the old kernel if the
new one does not work.

Self Assessment

Fill in the blanks:
1. An ............................................ package consists of an archive of files and meta-data used to
install and erase the archive files.

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